cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A246484 Number of length 5+3 0..n arrays with no pair in any consecutive four terms totalling exactly n.

Original entry on oeis.org

2, 38, 1420, 11020, 92478, 415650, 1756472, 5497304, 16089370, 39798430, 93260292, 196688868, 397729430, 748819610, 1364059888, 2360459440, 3978481842, 6452033814, 10241689340, 15777507260, 23878671982, 35285572498, 51371705640
Offset: 1

Views

Author

R. H. Hardin, Aug 27 2014

Keywords

Comments

Row 5 of A246479

Examples

			Some solutions for n=5
..5....1....5....4....1....3....4....1....1....5....3....2....3....2....1....5
..5....1....1....2....0....3....4....2....1....2....1....0....3....1....2....4
..2....3....5....0....1....4....0....5....0....2....3....0....1....2....5....4
..5....3....1....0....2....3....3....5....0....5....0....0....1....0....2....3
..1....3....2....1....2....0....3....2....1....4....1....3....0....1....5....5
..1....4....2....1....2....3....0....2....0....5....0....0....0....1....5....5
..3....0....5....0....1....3....0....4....1....5....2....1....3....3....5....4
..0....4....4....3....5....4....0....4....3....3....0....1....1....1....5....3

Links

Formula

Empirical: a(n) = 3*a(n-1) +3*a(n-2) -17*a(n-3) +3*a(n-4) +39*a(n-5) -25*a(n-6) -45*a(n-7) +45*a(n-8) +25*a(n-9) -39*a(n-10) -3*a(n-11) +17*a(n-12) -3*a(n-13) -3*a(n-14) +a(n-15)

A246485 Number of length 6+3 0..n arrays with no pair in any consecutive four terms totalling exactly n.

Original entry on oeis.org

2, 52, 3132, 31104, 347934, 1893780, 9714968, 35251360, 119069850, 331355220, 869135892, 2019732192, 4480392182, 9156814324, 18041010864, 33514806720, 60460359858, 104364198900, 175893704300, 286474229440, 457427541582
Offset: 1

Views

Author

R. H. Hardin, Aug 27 2014

Keywords

Comments

Row 6 of A246479

Examples

			Some solutions for n=4
..2....3....0....1....4....1....1....0....4....4....1....3....2....4....2....0
..3....4....3....1....3....1....0....0....4....4....1....0....0....4....4....2
..3....2....3....1....3....4....1....1....3....4....4....2....0....2....3....1
..3....3....2....2....3....2....1....1....3....3....1....3....3....3....4....1
..2....4....4....4....3....4....1....1....2....3....1....3....3....4....3....1
..0....3....3....1....3....4....1....1....3....2....1....3....3....4....4....1
..0....2....3....4....4....4....4....2....4....4....1....3....3....4....4....2
..1....3....2....1....3....4....1....4....4....4....1....2....3....3....4....1
..0....3....0....2....4....2....1....4....2....4....4....3....4....4....3....4

Links

Formula

Empirical: a(n) = 3*a(n-1) +4*a(n-2) -20*a(n-3) +56*a(n-5) -28*a(n-6) -84*a(n-7) +70*a(n-8) +70*a(n-9) -84*a(n-10) -28*a(n-11) +56*a(n-12) -20*a(n-14) +4*a(n-15) +3*a(n-16) -a(n-17)

A246486 Number of length 7+3 0..n arrays with no pair in any consecutive four terms totalling exactly n.

Original entry on oeis.org

2, 72, 6908, 87888, 1309038, 8628792, 53733080, 226048032, 881180090, 2758803240, 8099880852, 20739933552, 50471282918, 111972509208, 238609813808, 475857371712, 918806537970, 1688132007432, 3020848830380, 5201549128080
Offset: 1

Views

Author

R. H. Hardin, Aug 27 2014

Keywords

Comments

Row 7 of A246479.

Examples

			Some solutions for n=4
..1....0....4....2....1....2....4....1....0....2....3....0....2....3....3....4
..0....0....3....4....1....4....1....1....2....1....3....3....3....0....2....1
..0....2....3....1....1....3....1....1....3....0....0....0....3....0....0....2
..2....1....3....1....2....3....1....2....3....0....3....2....0....0....3....4
..1....1....0....1....0....3....4....0....3....0....3....3....2....1....0....1
..1....1....0....1....0....3....4....1....4....1....3....3....0....0....2....1
..1....4....0....1....3....4....1....0....3....0....3....4....0....2....0....1
..4....4....2....1....0....2....2....2....2....1....0....4....3....0....0....2
..1....1....0....1....0....4....1....0....3....2....3....4....3....1....3....1
..2....2....1....0....3....4....0....3....0....0....0....2....3....1....3....0

Links

Crossrefs

Cf. A246479.

Formula

Empirical: a(n) = 3*a(n-1) +5*a(n-2) -23*a(n-3) -4*a(n-4) +76*a(n-5) -28*a(n-6) -140*a(n-7) +98*a(n-8) +154*a(n-9) -154*a(n-10) -98*a(n-11) +140*a(n-12) +28*a(n-13) -76*a(n-14) +4*a(n-15) +23*a(n-16) -5*a(n-17) -3*a(n-18) +a(n-19).
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